(Reuters) - Marnus Labuschagne rode his luck to reach a half-century and push Australia to 154 for three at tea on day one of the fourth test decider on Friday, as India's injury crisis deepened on a hot and steamy day at the Gabba.
Labuschagne was 73 not out, with Matthew Wade on 27 at the break, after Australia won the toss and elected to bat on a pitch showing a surprising array of cracks.
Already decimated by injuries, Ajinkya Rahane's makeshift attack were a man down soon after the lunch break as paceman Navdeep Saini came off the ground with a groin strain.
He broke down in his eighth over following a delivery that Labuschagne nicked to Rahane in the gully, only for the India captain to spill the regulation chance.
The Australia number three was reprieved on 37 on that ball, and again on 48 when he nicked to Cheteshwar Pujara, who put down a tough, low chance at first slip.
Labuschagne pushed a single to mid-on to bring up his fifty.
It was galling for India, who had earlier celebrated the key wicket of Steve Smith for 36 when the master batsman was caught at short midwicket off debutant Washington Sundar's first ball of his first spell after lunch.
Despite four forced changes to their 11 from Sydney, India had stunned Australia with two early wickets in a dream start before Smith and Labuschagne steadied the ship for the home side in the morning.
With pace spearhead Jasprit Bumrah and spinner Ravichandran Ashwin ruled out, India blooded two debutants in fast bowler T. Natarajan and spin-bowling all-rounder Sundar.
Rahane's rookie, four-prong pace battery enjoyed a fine opening hour.
Two-test paceman Mohammed Siraj had David Warner caught for one with the sixth ball of the morning, a pearl of a delivery that induced an edge to Rohit Sharma, who dived across to his right from second slip to take a brilliant, low catch.
First change seamer Shardul Thakur, included for only his second test, struck with his first delivery when recalled opener Marcus Harris (5) senselessly flicked an innocuous ball off his pads straight to Sundar at square leg.
Among India's other changes, top order batsman Mayank Agarwal was recalled to replace Hanuma Vihari, who suffered a hamstring strain in Sydney. All-rounder Ravindra Jadeja was forced out earlier in the week with a broken thumb.
Australia made one change from the Sydney test, with Harris replacing injured opener Will Pucovski.
Australia have not lost a test at the Gabba since 1988 and will be confident of sealing the series 2-1 with their superior manpower.
(Editing by Peter Rutherford)